December on the calendar signals most of us to pull out the winter clothes, shop, cook and clean for the upcoming holidays, and fit in those last-minute doctor visits to use up the money in our flexible spending accounts.

Amid all those activities, we may skimp on exercise time, spend more of that time indoors and find a cold, sore throat or other ailment settling in occasionally. One simple thing to do to keep ourselves healthy during this hectic time is to check the humidity in our homes and workplaces.

Not only do most homeowners and employers tend to keep indoor humidity low to prevent the growth of mold and bacteria, but winter indoor temperatures are often cranked up high, especially in high-ceilinged areas, and those higher temps lead to lower humidity, sometimes under 20 percent relative humidity (RH). What does that mean for you? Less comfort, more susceptibility to germs and disease.

In a room with low humidity, moisture from your skin will evaporate at a faster rate, causing you to feel cooler—the same thing that happens when we sweat in hot weather to cool down. If you'd like to feel warmer this winter and save money on heating bills, buy a humidifier or two."Cool mist" or ultrasonic humidifiers put an impressively large amount of moisture into the air in a fairly limited amount of time, and are energy efficient. Investing the $25-75 for a humidifier can result in savings on your heating bill by not cranking the furnace up for comfort. Place one in every bedroom (most are very quiet, but if you can't fall asleep with one running, run it during the day with the door closed to humdify the room, then turn it off when you go to bed).

A simple bowl of water near the vents which push warm air into a room will help humidify the air as well. Just make sure it's placed where it can't easily be knocked over; a wide windowsill or shoulder-height shelf works well. (At work, you may have to find an out-of-the-way spot underneath your desk). If you have an older home with radiators (common in many Baltimore neighborhoods), simply set the bowl on top of the radiator. You may need to use a tray, cutting board or platter for support on the radiator's ribs.

In addition to helping you feel warmer and saving you money on heating costs, keeping the humidity in your home at a higher level in the winter can also be beneficial to your health. Breathing dry air can lead to such ailments as bronchitis, sinusitis, asthma, nosebleeds, colds, flu and dehydration. Dry air can also cause dry skin and eye irritation.

Flu viruses survive longer and are more easily transmitted when humidity levels are low, such as in the peak flu months of January and February, Oregon State University researchers say. "Outbreaks of influenza typically occur in winter when low absolute humidity conditions strongly favor influenza survival and transmission," said study author Jeffrey Shaman, an atmospheric scientist at OSU who specializes in ties between climate and disease transmission.

Interestingly, in Baltimore, relative humidity (which varies with temperature), is relatively stable throughout the year, but varies dramatically between morning and afternoon. Humidity in the morning ranges from an average high of 85 percent in September to a low of 72 percent in February, March and April. But in the afternoon, that number drops to a high of 57 percent in December and January; it dips as low as 49 percent in April. The problem, of course, is that we tend to air condition our homes in summer to remove excess humidity and overheat in winter, drying the indoor air to levels well below the outdoors.

If you Google “ideal indoor humidity”, you’ll find most sources advise trying to keep it right about 45%. Below 30%, you get increased risk of dry skin, respiratory infections, static electricity, and ozone. Above 55% you have increased risk of condensation, fungus and mites. Bacteria and viruses allegedly become more prevalent both above and below this range, as do risks of allergies and asthma. Here’s a nice chart, based on this complex report from the Technical Resource Center of Finland:

So do yourself a favor: step outside more often and humidify your indoor air for better health.

Saturday's weather was beautiful, enticing many outside to take a walk, wash the car or run. Nearly 26,000 showed up for the Baltimore Running Festival and women outnumbered men in every race: the marathon was 62 percent women, the half-marathon was 59 percent, the 5K was 65 percent women and the relay was 62 percent. Less than 10 years ago, only 44 percent of the participants in the running festival were women.

So what accounts for the upsurge? Like so much else in society, it's social. Women, more so than men, run as a group. They chat on training jogs, they invite friends, cubicle-mates and relatives, and most of all, they support each other. Although there are certainly many fiercely competitive women out there aiming to beat a course time (and a bunch of the men, to boot), the majority of women are running not for race day glory but for personal achievement.

That could be to overcome personal health challenges, to honor a friend or relative's battles with chronic illness or simply to carve out some mental health time away from the pressures of family and profession. Having the camaraderie of a group of sole sisters makes training less of a slog and offers built-in support and encouragement when the going gets tough and the goal seems unreachable.

Even having just one person to beside you makes a difference, which is why many who have tried fitness activities in the past and failed to stick with it look for a personal trainer, whether the goal is simply weight loss or to run a 26-mile race. I make it a point to keep up with the latest fitness research and to understand the nutrition consequences of various ways to fuel your body for different activity levels.

It's fabulous to have a goal such as participation in a race—it gives you a deadline to prepare for and a community of others who've done it before and can share their successes and mistakes. Although running races are not everyone's cup of tea, more and more people are discovering that the simplest of human activities—walking and running—can provide both pleasure and satisfaction.

Congratulations to all the participants of the Baltimore Running Festival! Next time, I'll share some ideas on training for injury prevention.

Beautiful fall day today, perfect for a workout with a client in Druid Hill Park. This gem in northwest Baltimore City has rolling hills, lovely old trees, a paved path around one of the city's reservoirs, a conservatory and the zoo. Many people were walking or jogging around the reservoir, whose pathway has a number of workout stations for such things as pullups, situps, balance, etc.

Instead, we trained on the lawns, between the trees and around the gardens with sprints, push-ups, fast and slow walks. A great way to challenge the body with more variety of muscle recruitment than is possible on any paved surface.

One of the things I asked my client to notice is the difference in her body between walking on the paved trails and on the grass. Immediately, she noted that there was less impact on her hip joints and her legs were working harder on the grass.

I advocate getting off the pavement and onto the adjacent grass as much as possible to all my clients who enjoy either walking or running. The foot and ankle contain 26 bones (one-quarter of all the body's bones), 33 joints and more than 100 muscles, tendons and ligaments. Yet we typically constrain this marvel of anatomy into a rigid shoe and then pound it continually into an unyielding surface. Many of the muscles of the foot, ankle and lower leg get little to no workout under this scenario, thus leading to muscle imbalances, which can manifest as loss of flexibility, weakness in certain postures and movements and, ultimately, in injury.

So, two thoughts: First, get outside to be active whenever you can. Cuts boredom, allows fresh air into your body and the beauty of nature is a wonderful, calming antidote to a hectic, stressful life.

Second, try the grass instead of the pavement. Even the most manicured lawn or the most minimally-planted contractor-grade landscape will provide your feet and ankle with variation in grass height/springiness and ground level. The resulting adjustments your body makes will strengthen and energize you.

Janet is a Certified Personal Trainer with ACE, the American Council on Exercise, as well as a Maryland state and nationally certified
Licensed Massage Therapist. Janet is passionate about integrating physical, emotional and spiritual health and wellness into her own life and the lives of her clients. She enjoys walking and hiking and has backpacked, biked, canoed and had week-long outdoors adventures, camping in all kinds of weather, with her son's Boy Scout troop. She is a Master Gardener and grows her own medicinal herbs. Whether you are currently physically active and just looking for strategies to take you to the next level, just contemplating incorporating more movement and activity into you life or recovering from injury, Janet can help you be Fit For Life!